What does hdr mean?

HDR stands for high dynamic range imaging.

High dynamic range imaging (HDRI or HDR), in computer graphics and cinematography, is a set of techniques used to achieve a larger exposure dynamic range (that is, a greater difference between light and dark) than ordinary digital imaging techniques. The purpose of high dynamic range imaging is to correctly represent the brightness in the real world from direct sunlight to the darkest shadow.

High dynamic range imaging was originally used only for images generated purely by computers. Later, people developed some methods to generate high dynamic range images from photos with different exposure ranges. With the increasing popularity of digital cameras and the simplicity of desktop software, many amateur photographers use high dynamic range imaging to generate photos of high dynamic range scenes.

HDR application scenario

Light photography: Because landscape photography often faces images with large light ratio, it is very suitable for HDR technology. Still life photography such as flowers and plants: this kind of subject matter is rich in color change and light and shadow, and it is still at the same time, which is conducive to early shooting. Sunset, sunrise and night scene are all good subjects for shooting HDR: the contrast between sky and landscape is great, and the dynamic range of digital camera can not meet such a large dynamic range, so it is the most suitable application subject for HDR.

When shooting indoors, the picture includes dark scenes indoors and very bright scenes outdoors, so that both indoor and outdoor scenes can be well displayed in this picture. In short, as long as the picture is relatively stable and the contrast between light and dark is large, it is all taken by HDR and synthesized by HDR post-processing.